environmental control of metabolisn

• microorganisms are highly adaptable and are used because of their ease of cultivation
• when culturing microorganisms:

  sterile conditions are required - other cells compete or resources so ##reduces spoilage of product

  temperature - thermostatically controlled containers

  oxygen levels - aeration

  pH - adding buffers

  microbes are grown by fermenters and sensors detecct changes
• lag phase - there is little increase in cell number as enzymes are being introducedd
• log phase - the cells grow and divide at their maximum rate due to plentiful nutrients
• stationary phase - the production rate and death rate are equal so population stays the same size. because the culture medium has become depleted of nutrients and secondary metabolites are building up
• death phase - number of cells dying exceeds new cells being produced